1-substituted-2, 5-diketo-7-methylpyrimidopyrazoles and process of preparing the same



prepare 1-Substtutedra5f -rirnidopyrazolesusefulEas colori-.formers for. producing. blue dye images by colorrforming development Patented Sept. 6, 1949 UNITED srArrE-s PATENT E Abraham Bavley,l Binghamton,- N .j. assign ornto v `GeneralAniline & -IFilm Corporation; New/york, `N. Y., acorporation 0f Delaware No.Drawing. Application November 1721.19.44,

Serial No.'6,3,9.74'

, 13 Claims.

AThis invention relates to -1substituted2,5

--diketo-f-methyl-pyrimidopyrazoles and to a process for-preparing"the'sarne.

It is known inthree-co-lor photography that the key image isV the blueorblue-green image which is produced; inthe-red-sensitive layer. It has Ybeen thepracticeyin'the art to produce such images, particular-lyl` in. color-forming development-methodsby A`thef utilization of avphenol.

On -thefother-.handit has been the practice toy v produce the -magenta image by'employng cornpounds which contain a reactive methylene group, usuallyA a pyrazolone. -I have -now ydiscovered that -the Vvreaction products lofl diketene with a pyrazolone Which contains a Yprimary Y amino.

groupron- `thecarbon -atom in 3-position and a substituentwmv themitrogen atom in l-position v'give blue f images on color-forming development despite the 4f-ac'ztf-thatsuch compounds-still contain a reactivemethyleneI group and arefree Vfrom phenolic hydroxyl groups.

This result is surprising-,gior it was to be expected'that-the compounds, due to the presence .of thereactiVe-methylene group, would react in color-forming development in the sameV mainner.'iy

asthe pyrazolones-to produce magenta or purple images.

The compounds whichpare lproduced hy this reaction`v are 1-substituted-Z,-diketo-'Z-rnethylpyrimidopyrazoles. fFIfhe'reaction vleading totheyi formation-ofthese Ac omllvllnds cannot take place by using any amino pyrazolone. On the contrary, vthas'N beenv ascertained-that unless the nitrogen atom in the l-position besubstituted and the primary amino group be in the S-.position it is impossible to obtaiqthedesired pyrimidopyra- Zoles. The `useof..cyr,z nzolones having the aforestated structure., is,r.therefore critical .to the. successful production of.; lthe. blue co1or.-for mers .of

the .present invention.

It is an.objectof thef prseninventon to ete-.7 .e methyl DY- .A further object/...of the,.invention is the said pyrimidopyrazoles. Y

. 4A'stillurfther 'bjectismo provide photographic .developersolutions andvemulsionswhich contain dw images@ situ with @membres wm.

presence aqueous..

a newness .9i .,QQlOarm'-rs;.ion-producing blu@ liotogrfajpliicY images.

pparent by. reference `eci@ation' in yvhich its pren d @mbo irnents., areA described.

c,'Iheunovel c mp' nys ofwthis invention are t riiarmamins ,Such as ine, etc., Sulioamno afomatl hxfaarlfm O1Q-an1oxygenated bon at agielarrlauraranging from.; 80 2 oursjto 5 hours.- fr' Insteadof wfo the reaction, the .A y, water andthe heated temperature ranging from 80 C. to 100 C. forgtllgsamaporod 0f time.

' Asxnirlgruitals ratiatum-Sammnes which condense. th'diketenefacmentioned. 1-

ample,

` ino--pyrazolone.

-pyrazolone and the like.

Various structuralformulae for diketene have been proposed in the literature (Ind. and Eng. Chem., 32, p. 16, 1940). Among the structures proposed are the following;

During the experimentationwith and-the practicing of this invention, I have discovered that the probable structure of diketene is immaterial since the commercially available dilgetenerl will'` condense with a 1-substituted-3-amino--pyrazolone to give a product characterized by a structure corresponding to the above general formula.

The 1-substituted-S-amino-5-pyrazolones employed as starting materials may be prepared in various ways. One suitable method which is described by Conrad and Zart in Ber., 39, 2282 (1906) consists of treating ethyl cyanoacetate with phenyl'hydraZine, using sodium' alcoholate as a condensing agent. Other suitable methods are described in the Jour. of Amer. Chem, Soc.; 64, p. 2133, 1942, and United vStates' Patent 2,343,704.

1 (a pyridyl) 2,5 diketo 7 methyl pyrimidopyrazole SGIVent, Suchl as, 1 N-a1coholic sodium or potassium hydroxide, acetone, ethyl alcohol, isopropyl alcohol,A etc. Dispersing agents such as isopropyl- 'naphthalene sulfonic acid or any of the dispersing agents disclosed in United States Patent 2,186,717

Y may be-used in preparing the suspension of the The condensation between the l-substituted-S- A amino--pyrazolone and diketene tolproducre the compounds of the present invention is vcarried out water insoluble color-formers for incorporation into developers or vsilver-l'lalide emulsions. Instead of gelatin, the color-formers Vmaybe incorporated in other colloidal-materials such as, organic esters tof cellulose, super-polyamides, polyesters or other syntheticresins.n The emulsion may be carried by a transparent medium such as cellulose esters, super-polyamides, synthetic resins or a non-transparent reflecting medium first, by dissolving the co-reactants in a suitable,

solvent-diluent such as a cyclic hydrocarbon, for example, cyclohexanecycloheptane, cycloctane, benzene, toluene, o, m, and p-Xylene, ethylbenzene, 1,2,4-trimethy1benzene, propylbenzene, 1,3-ethylmethylbenzene, an oxygenated hydrocarbon such as, ethyl methyl ketone, diethyl ketonemethyl Y propyl ketone, allylacetone,mesity1oxide, dioxane and the like, stirring the reaction mixture at room temperature for a period of time ranging from 15 minutes t'o 1 hour. The reaction mixture is then heated on a steam bath at a temperature ranging from 75 C. to 130 Clfor a period' of time ranging from 2 hours to 5 hours. The reaction mixture is then cooled, the precipitatedY product Washed with ether and recrystallized from methyl or ethyl alcohol. The ratio of the reactants is `one mol of l-substituted-B-amino-pyrazolone to 1 to 11/2 Inols of diketene. The desirable ratio of diketene, however, is in the range of` 1.2 mo'lsper one mol of 1-substituted--amino-pyrazolone 1 Of these various classes of solVent-dilue'nts, the aromatic hydrocarbons-are byfarthe most practical, and therefore preferred in'vievv of their relative cheapness. rIt to be'noted, however, that solvent-diluents Yother than Vabove mentioned may also be employed, the selection depending more or less on the resistance of the selected solventdiluent to react With diketene.V A l Specic Vcompounds which have'be'en prepared by the reactions hereinafter described are the following, it being understoodthat theyvare exemplary only and that they may contain other substituent groups as well asl thoseY in cluded in these compounds: f

1-methy1-2,5-diketo-7-methyl-pyrimidopyrazole 1ethyl-2,5-diketo-7-methyl-pyrimidopyrazole 1propyl-2,5diketo-7-methyl-pyrirnidopyrazole l-phenyl-2,5diketo-7-methyl-pyrimidopyrazole 1.-ptolyl2,5 -diketo7-methyl-pyrimidopyrazole 1-otolyl-2,5 -diketo-7-methyl-pyrimidopyrazole such as paper, or anropaque cellulose ester. The

emulsion may be coated as a ,single layer onthe support, 'or vsuperposedlv layers containing the `couplers may be coated on, one orlbothsides of the support. vThe superposedlayers may be differentially sensitized for the formation of a color image in the well-known manner.

When incorporating the color-farmers into photographic silver-halide emulsions, itis essential that the substituent of-the R group in the above general formula besuch that it will preventY the color-formers from migrating fromrone layer to another, otherwise color ydistortion will result upon color-forming development, v Several; methods have been proposed to preventmigration of colorforrners from silver-halide emulsion layers by rendering such color-formers .fast to diiusion in gelatin. This result may be accomplishedin several Ways, as for example, by substituting the R group with suitable groups which impart substantive characteristics to the color-formers whichY combine permanently with thegelatin and other colloidal materials-of,thersilver-halide emulsion, or by enlarging the substituent group of the color-former withY va long chain alkyl radical so that the color-former is, incapable of `diffusing from the gelatin or othercolloidal material. Examples of such methods Whic'hrender-colorformers fast to diffusion by imparting substantive characteristics theretof'ar'e disclosed in United States Patent 2,179,228. Examples of colorformers which are rendered fast to diffusion by enlarging the substituent group aredisclosedin United States Patents 2,175,512; 2,178,612; 2,179,244; 2,1'l'9,2.':a"1',"V 2,179,233-9; 2,179,344; 2,186,045;v 2,186,719; 2,186,732-3-4; 2,186,849; 2,186,851-2; 2,209,306; 2,280,722, f 2,292,575;

2,303,928 and 2,307,399. By reference to the latter patents, it willgbe noted that the color-formers are modii-ledby the inclusion of radicals of resins, polypeptides, hydrogenated Vring systems,Y carbohydrates, long alkyl Y chains,= and- Vby having z the substituent radical recurar-rumer of'times-.lnr the iinal molecule. It is to be understood: 'that the substituent group of.' the., icoloreformers. of the present; invention, in.. addition to; those previously mentioned-',.i-nclude substantivef'group's lor molecular enlarging groups-fair the-'ipuhrpose'of renderin'g thef 2f,5ediketc?'lzemethylf-pyrimidopyrazoles fasttofdiiusion.

Asexamples of. i'suitable. aromatic .primary amino developing ragentswhic'lrmay be employed with. the color 'coupling i'coirnpounds ofthe present invention, there mayloer mentioned pephenylenediamine, monoy 'ethyl-pephenylenediamine, diethyl-fphenylenediamine, 1,;4"-'diairrlnod-iygihenylamine,.;paminodialicylaniline; ef. lg., .p-amin'odimethylanilineandp-aniinodiethylaniline; These. developing lagents areipreierably usedinthe form ofi their saltsl su'ohv ias. the ll'iiydrochloiid'e, lsince they are more soluble and stable than the free bas'e. Theyare characterized-bythe iprese'nce-of a lfree `or primary amino/group Ai'n the phenyl nucleus. which'enaloles the `oxidation product 'of the developer to.y couplefvtith. itheffoolor-iormer to. -iorm @adye image A-lnthe mulsion 'adaiaoent to the individual particles of the silver image.A The silver vimage 'may be removedfiby. bleaching inthe vxelleknown manner to leave 'the color image in the emulsion.

A` suitable 'developing-solution Visz .prepared 4asv follows-2 p-Aminodiethylaniline HC1,.-- gramse 2.0 Sodium carbonate (afxilr1`yidrous). dou- 50.0.y Sodium sulte (anhydrous) f do 20 Potassium bromide do 0.2 Water to -malse l litera-' v1 veloped/in Ithe above solution lif'n theusual 'manner. A solution or suspension of the color-former is only added lto 'the developing solution Vwhere the vcolo'rformer ei's not present the silverhalide emulsion.

The following, examples are intended to illustrate th'e -preparationlbf compounds disclosed above. It willbeappreciated thatthe conditions of reactions, 'e. g., 'proportioh of"'reacting ing-re'dients, times. -of4 reaction, anda `tempera-ture, may be varied and that supplementarysprocesses of purication. and the like. may. be. resorted to wherever found 'desirable Tlie'se 'a'nd other variations and modifications/Will be evident :to those skilled' in. they art in 'f-liht'of theg-uiding principles fdisclosed. herein.v

Example I 1-phenyl-2,5-diketo-7-methyl-pyrimid0pyrazole l CH3 To 4 grams of 1-phenyl-3-amino--pyrazolone in 25 cc. of dry xylene, a solution of 3 grams of diketene in cc. of dry xylene was added slowly with constant stirring. The mixture was stirred at room temperature for one-half hour and then heated on a steam bath at 100 C. for 2 hours. The reaction mixture was allowed to cool, the precipitated product ltered and Washed several 6K times with ether, and recrystallized fromvmetliyl alcohol.

One gram of the above product was dissolved in 20 cc. of ethyl alcohol. Two cc. of the solution was then added to the developing solution and used for the development of an exposed silverhalide emulsion. An excellentr blue image was obtained together with 'the silver image.

EztctmpleA II 1- (p-tolyl') 2, 5sdiketo-7-methyl-pyrimiddpyrazole To 4.5 grams of 1-(p-tolyl) -3-amino5 pyrazolone in 35 cc. of dry xylene, a solution of e grams of diketene in 215 cc. oi dry xylene was added. The mixture was stirred at room temperature tor 45 minutes-and then *heated fon" a` steam bath at 100 C. for 21/2 hours; re'- action mixture was allowed to cool, the precipitated product iiltered and washed several times with ether, and recrystallizedi from methyl alcohol.

One gram of the above product was dissolved in 20 cc. oi ethyl alcohol. Two cc. of the solution ,y was then added to the developing solution and used for the development of an exposed silverhalide emulsion. A11 excellent blue image was obtained together with the silver image.

Evample III 1- a-quinmyi) -2[5diketoirmethyipyrimidnpynamm To 11.3 grams of 1- (alphafquinolyl) 3.amino5 pyrazolone in cc. oiV 'd1'"y^xylen"e,vk a sdllitionof. 5l2 grams of. diketene in20}'c'c. of dry. Xylenewas. added. The Amixture was 'stirred'. a'tjrfoom tem.- perature for 45 minutes aiidthen 'heated on a steam bath at C. for 21/2 hours. The reaction mixture was allowed to cool, the precipitated product filtered and washed several times with ether, and recrystallized from methyl alcohol.

One gram of the above product was dissolved in 20 cc. of ethyl alcohol. Two cc. of the solution was then added to the developing solution and used for the development of an exposed silver-halide emulsion. An excellent blue image was, obtained together with the silver image.

While the present invention has been described in considerable detail with reference to certain preferred procedures, materials and uses, it ils to be understood that the class of compounds and their application is not limited thereto, and that all relative modifications and variations are within the scope of the invention as dened by the appended claims.

7 Iclaizm 1. Chemical compounds of the general formula: f

:51/ IJ `CH1 5 HC\ N =O \(|J/ \N/ `CH3 lll wherein R is selected fromthe class consisting Qi alkyl of not more than 24 carbon atoms, aryl, aralkyl and unsubstituted mono-ntro'genous heterocyclic groups.

2. The chemical compound corresponding to the formula:

l 3. The chemical compound corresponding to the formula:

4. The chemical compound corresponding to 4 the formula:

prises heating a 1-substituted-3-amino-5-pyrazolo'ne with diketene and recovering the said 1- 8 substituted-2,5-diketo-l-methyl p'yrimidpyrazoles so formed. y Y

6. The process Vof producing 1-substituted-2,5 diketo-7-methyl-pyrimidopyrazoles which comprises heatingrr one mol of al 1substituted3 amino-5-pyrazolone with 1- to 11/2 mols of diketene and recovering the said 1-substituted2,5 diketo-7-methyl-pyrimidopyrazoles so formed.

'7.` The YprocessV of producing 1phenyl-2,5 diketo-7-methyl-pyrimidopyrazole which com. prises heating V1 -pheny1-3-amino--pyrazolone with diketene and recovering the said l-.phenyl- 2,5-diketo-'I-methyl-pyrimidopyrazole- 8. The process of producingl-(p-tolyl)2,5

Ydik-eto-7-me1'hy1-pyrirnidopyrazole which comprises heating 1-(p-to1yl) -3-amino-5-pyrazolone. with diketene and recovering the said 1- (p-to1yl)2,5 diketo-7`- methyl pyrimidopyrazole.

9. The process of producing l-(a-quinolyD- 2,5 diketo 7 methyl pyrimidopyrazole which comprises heating 1 (a quino1y1)3amino5 pyrazolone with diketene and recovering the said l-(a-quinolyl)2,5diketo7 methyl pyrimidopyrazole.

10. The process according to claim 5 wherein the heating is conducted in the presence of an inert solvent-diluent, a member selected from the class consisting of water, aromatic hydrocarbons and aliphatic ketones, at a temperature ranging from to 130 C. y y

111. The process according ,tov claim '7 wherein the ratio of'reactants heated is one mol of 1- phenyl-B-amino--pyrazole to 1.2 mols of diketene.

12. The process according to claim 8 wherein the ratio of reactants heated is one m01 of l-(ptolyl) -3-amino-5V-pyrazolone to 1.2 mols of diketene.

13. The process according to claim 9 wherein the ratio of reactants heated is one mol of l-(vr-V quinolyl) -3-a1nino-5-pyrazo1one'to 1.2 mols of diketene. Y Y

1 I ABRAHAM BAVLEY.

REFE'RENoEs CITED The followingl references are of record in the me of this patent:

UNITED .STATES PATENTS Number Name Date 2,303,928 Frohlich et al. Dec. 1, 1942 2,343,703 Porter s Mar. 7, 1944 2,343,704 Porter Mar. 7, 1944 2,369,489

P01ter..' Feb. 13, 1945 

